The present invention relates generally to a method and apparatus by which a compressible and cohesive material may be compressed, densified and formed into a discrete solid block for disposal or other uses.
While the present invention is applicable for use with virtually any material that is compressible and sufficiently cohesive to remain in a compressed state after being pressed into such state, it is particularly applicable in a variety of manufacturing and processing operations which generate a high volume of waste or by-products that must be handled in an environmentally safe manner that is also efficient and cost-effective. For example, in various textile plants, a large quantity of lint and other textile waste is generated which must be disposed of, and because of its open and fluffy characteristics, it occupies a large volume and poses a particularly difficult problem in terms of temporary storage and ultimate disposal.
It is known to compress materials such as textile waste, saw dust, and the like into discrete solid blocks utilizing so-called briquetting machines like those described in Klias U.S. Pat. No. 5,059,372 and German Patent No. DE 33 33 766 C2, whereby a high volume of such material is compressed into a relatively small and dense briquette that is easy to handle, transport, and dispose of or use for varying purposes (e.g. as fuel).
As described in greater detail in the above-described patents, these known machines generally include a compression chamber having a portion in which material to be compressed is fed from a hopper and a pre-press ram is used to initially compress the material after which a main ram is moved into the chamber to complete the densifying and compression of the material so that it is formed into a briquette or discrete solid block and then ejected from the machine, after which the cycle is repeated.
In these known machines, the material is fed to the compression chamber at a generally fixed flow rate by a rotatable auger which is rotated a predetermined number of revolutions during each cycle of operation. It has been found, however, that in some situations, such as for example in dealing with the textile waste materials described above, the waste may come from different parts of a textile mill or plant, and, in many instances, the individual components that make up the waste will vary in density, size and concentration levels so that at any given time during the cycles of operation of the machine it may be compressing material that has a different overall density than at other times during the operation. Since the auger is delivering the material to the compression chamber at a generally constant flow rate, the variations in the make up of the waste can, and often do, cause the machine to operate in either underload or overload conditions, and while there are subsystems within the machine that will enable it to operate despite underload or overload ("upset") conditions, these subsystems nevertheless operate at the expense of the production rate of the machine, and in some cases the machine will shut down if too many "upset" conditions occur within a given period of time.
In accordance with the present invention, the above-described drawbacks of known briquetting machines are alleviated or cured by an automatic feed compensation system that maintains a substantially consistent briquette size, and therefore maintains a substantially constant and efficient production rate for the machine.